1. Field of the Invention
This invention relates to a fitting structure of partition plates to a structure.
2. Description of the Related Art
A sewage disposal tank is an example of the structures using a fitting structure of partition plates to a structure. To divide the inside of a tank body into a plurality of treatment chambers, the sewage disposal tank employs the construction wherein end portions of partition plates are fitted into, and bonded to, a groove formed along the inner periphery of the tank body through a sealing material.
In the sewage disposal tank described above as an example of the prior art, however, a normal treating function might be inhibited when untreated sewage in a treatment chamber of a pre-stage leaks from a fitting gap between a groove and partition plates and mixes with treated sewage in the treatment chamber of a post-stage, for example. To prevent such a problem, seal must be effected in such a manner as to satisfy two conditions, that is, sufficient bonding strength of the partition plates to the groove and sufficient water-stopping strength between them.
To secure the sufficient bonding strength, it is effective that the sealing material exists in the form of a thin film between the surfaces to be bonded, and to secure sufficient water-stopping strength, it is effective that the sealing material exists in the form of a thick film, on the contrary. To make positioning of the fitting positions of the partition plates to the groove easy, the groove and the end portions of the partition plates are generally finished into a tight fitting state and for this reason, the thin film of the sealing material is naturally interposed and the sufficient bonding strength can be secured. In contrast, since the thick film of the sealing material is not obtained, there remains the problem that the water-stopping function is low.
Accordingly, the structure described above is far from suitable as a partition plate fitting structure of a structure in which water leakage must not occur, such as the sewage disposal tank.